The general syntax of the grep commands is: You can use fgrep to find all the lines of a file that contain a particular word. For example, to list all the lines of a file named myfile in the current directory that contain the word dog, enter at the Unix prompt:
Outer core. The outer core of the Earth is a liquid layer about 2,300 km (1,400 mi) thick and composed of iron and nickel that lies above Earth's solid inner core and below its mantle.Its outer boundary lies 2,890 km (1,800 mi) beneath Earth's surface.ecause of its high temperature, modeling work has shown that the outer core is a low viscosity fluid (about ten times the viscosity of liquid metals at the surface) that convects turbulently. Eddy currents in the nickel iron fluid of the outer core are believed to influence the Earth's magnetic field.
Earthâs Outer Core. The outer core is the liquid largely iron layer of the earth that lies below the mantle. Geologists have confirmed that the outer core is liquid due to seismic surveys of Earthâs interior. The outer core is 2,300 km thick and goes down to approximately 3,400 km into the earth.